In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep le...In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep learning has focused on single-layer grating couplers,and the accuracy of multi-layer grating couplers has not yet reached a high level.This paper proposes and demonstrates a novel deep learning network-assisted strategy for inverse design.The network model is based on a multi-layer perceptron(MLP)and incorporates convolutional neural networks(CNNs)and transformers.Through the stacking of multiple layers,it achieves a high-precision design for both multi-layer and single-layer raster couplers with various functionalities.The deep learning network exhibits exceptionally high predictive accuracy,with an average absolute error across the full wavelength range of 1300–1700 nm being only 0.17%,and an even lower predictive absolute error below 0.09%at the specific wavelength of 1550 nm.By combining the deep learning network with the genetic algorithm,we can efficiently design grating couplers that perform different functions.Simulation results indicate that the designed single-wavelength grating couplers achieve coupling efficiencies exceeding 80%at central wavelengths of 1550 nm and 1310 nm.The performance of designed dual-wavelength and broadband grating couplers also reaches high industry standards.Furthermore,the network structure and inverse design method are highly scalable and can be applied not only to multi-layer grating couplers but also directly to the prediction and design of single-layer grating couplers,providing a new perspective for the innovative development of photonic devices.展开更多
We experimentally investigate the effective working regions of a planar-integrated magneto-optical trap(MOT).By scanning a blocking point in the incident laser beam,we identify four effective working regions of the la...We experimentally investigate the effective working regions of a planar-integrated magneto-optical trap(MOT).By scanning a blocking point in the incident laser beam,we identify four effective working regions of the laser beam contributing to MOT:a central region corresponding to the downward incident beam and three regions associated with the upward diffracted beams.The latter three regions are the effective regions of the grating chip.It is demonstrated that only three3.5 mm radius grating regions can produce a MOT that is capable of trapping 105atoms with a temperature below 150μK,retaining over 60%of atoms compared to a complete grating chip.This finding suggests that more than 60%of the grating chip area can be saved for other on-chip components,such as metasurfaces and nanophotonic devices,without significantly compromising MOT performance,paving the way for more compact and versatile atom–photon interfaces.展开更多
A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged ...A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged in a uniform and regular way,but its spacing can be larger than that of traditional arrays.An ideal model of the offset phase center element is established and its far-field distribution is derived.To suppress grating lobes,the phase center of any element is designed to be movable without changing its physical position.Using genetic algorithm(GA),a new constraint condition limiting the number of phase center changes is proposed to solve the objective function of the minimum values of grating lobes(GLs)and side lobes(SLs).It is shown that the optimal results can be achieved by two changes of phase centers.A multimode circular patch is developed and designed,and characteristics of the offset phase center are analyzed and verified.A prototype array of 12×12 offset phase center elements is implemented based on multi-mode circular patches.Full wave simulation results of radiation patterns show that the level of grating lobes is suppressed at least 7dB with 1.12λ spacing,while the scanning angle is 20°.展开更多
Particle accelerators are indispensable tools in both science and industry.However,the size and cost of conventional RF accelerators limits the utility and scope of this technology.Recent research has shown that a die...Particle accelerators are indispensable tools in both science and industry.However,the size and cost of conventional RF accelerators limits the utility and scope of this technology.Recent research has shown that a dielectric laser accelerator(DLA)made of dielectric structures and driven at optical frequencies can generate particle beams with energies ranging from MeV to GeV at the tabletop level.To design DLA structures with a high acceleration gradient,we demonstrate topology optimization,which is a method used to optimize the material distribution in a specific area based on given load conditions,constraints,and performance indicators.To demonstrate the effectiveness of this approach,we propose two schemes and design several acceleration structures based on them.The optimization results demonstrate that the proposed method can be applied to structure optimization for on-chip integrated laser accelerators,producing manufacturable structures with significantly improved performance compared with previous size or shape optimization methods.These results provide new physical approaches to explore ultrafast dynamics in matter,with important implications for future laser particle accelerators based on photonic chips.展开更多
A modified multiwavelength actively mode-locked fiber ring laser is proposed and experimentally demonstrated. In this kind of laser, stable multiwavelengths lasing is achieved by integrating cascaded sampled fiber Bra...A modified multiwavelength actively mode-locked fiber ring laser is proposed and experimentally demonstrated. In this kind of laser, stable multiwavelengths lasing is achieved by integrating cascaded sampled fiber Bragg gratings(SFBGs) into the laser cavity. To implement actively mode-locking technique, a double-ring cavity configuration is used to assure that the cavity lengths for all wavelengths lasing are identical. Thus, simultaneous mode locking of all wavelengths has been successfully achieved by using the same mode-locking signal.展开更多
This paper introduces the design and applications of integrated As2S3 sidewall Bragg gratings on LiNbO3 substrate. The grating reflectance and bandwidth are analyzed with coupled-mode theory. Coupling coefficients are...This paper introduces the design and applications of integrated As2S3 sidewall Bragg gratings on LiNbO3 substrate. The grating reflectance and bandwidth are analyzed with coupled-mode theory. Coupling coefficients are computed by taking overlap integration. Numerical results for uniform gratings, phase-shifted gratings and grating cavities as well as electro-optic tunable gratings are presented. These integrated As2S3 sidewall gratings on LiNbO3 substrate provide an approach to the design of a wide range of integrated optical devices including switches, laser cavities, modulators, sensors and tunable filters.展开更多
Effectively managing floods in urban regions requires effectively designed and well-maintained runoff collection system. The absence of such a system and intense rainfall event will have the potential to disrupt the u...Effectively managing floods in urban regions requires effectively designed and well-maintained runoff collection system. The absence of such a system and intense rainfall event will have the potential to disrupt the urban life and cause significant economic loss to properties. Grated inlets, which are a key component in urban drainage network, are used to capture the runoff. In this work, a three dimensional CFD model was developed based on open-source CFD tool, OpenFOAM®, to model flow over a grated inlet. An incompressible, transient, multiphase flow, Volume of Fluid (VOF) simulation was performed to predict the water flow rate through the grate inlet. The predicted flow rates are compared with the HEC-22 monograph values. The close agreement between the results shows the potential of using CFD modeling approach to test the reliability of existing drainage inlets for different flow scenarios.展开更多
In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever cou...In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever couplers,and optical wirebonds.In addition,technology for efficient transmission of light through chips is discussed including guided mode and free form photonic vias for substrates including silicon,glass,and organics.The results are discussed in the context of potential applications including co-packaged optics switch packages,replaceable biochemical sensors,optically connected memory,optical computing,integrated quantum photonics,and integrated LiDAR systems to show possible improvements in energy efficiency,performance,and cost.展开更多
This study proposes a novel heterodyne grating interferometer designed to meet the multi-dimensional atomiclevel measurement demands of next-generation lithography systems and large-scale atomic-level manufacturing.By...This study proposes a novel heterodyne grating interferometer designed to meet the multi-dimensional atomiclevel measurement demands of next-generation lithography systems and large-scale atomic-level manufacturing.By utilizing a dual-frequency laser source,the interferometer enables simultaneous three-degree-of-freedom(3-DOF)displacement measurements.Key innovations include a compact,zero dead-zone optical path architecture,which enhances measurement robustness by minimizing sensitivity to laser source instabilities and atmospheric refractive index fluctuations.In addition,we present a systematic crosstalk error analysis,coupled with a corresponding compensation algorithm,effectively reducing crosstalk-induced errors to below 5%.Experimental evaluation of the 90×90×40 mm^(3) prototype demonstrates outstanding performance metrics:sub-nanometer resolutions(0.25 nm for X/Y-axes,0.3 nm for Z-axis),superior linearity coefficients(6.9×10^(−5),8.1×10^(−5),16.2×10^(−5) for X-,Y-,and Z-axes,respectively),high repeatability(0.8 nm@1000 nm for all axes),exceptional long-term stability(20 nm XY-plane drift,60 nm Z-axis drift over 1000 s),and practical measurement ranges exceeding 10 mm inplane and 2 mm axially.Comparative analysis with state-of-the-art sensors demonstrates significant advantages in measurement precision,system integration,and multi-axis capability.This advancement highlights excellent potential for applications in integrated circuit fabrication,atomic-scale manufacturing,and ultra-precision metrology for aerospace systems.展开更多
Silicon photonics is an emerging competitive solution for next-generation scalable data communications in different application areas as high-speed data communication is constrained by electrical interconnects. Optica...Silicon photonics is an emerging competitive solution for next-generation scalable data communications in different application areas as high-speed data communication is constrained by electrical interconnects. Optical interconnects based on silicon photonics can be used in intra/inter-chip interconnects, board-to-board interconnects, short-reach communications in datacenters, supercomputers and long-haul optical transmissions. In this paper, we present an overview of recent progress in silicon optoelectronic devices and optoelectronic integrated circuits （OEICs） based on a complementary metal-oxide-semiconductor-compatible process, and focus on our research contributions. The silicon optoelectronic devices and OEICs show good characteristics, which are expected to benefit several application domains, including communication, sensing, computing and nonlinear systems.展开更多
Leveraging the low linear and nonlinear absorption loss of silicon at mid-infrared(mid-IR)wavelengths,silicon photonic integrated circuits(PICs)have attracted significant attention for mid-IR applications including op...Leveraging the low linear and nonlinear absorption loss of silicon at mid-infrared(mid-IR)wavelengths,silicon photonic integrated circuits(PICs)have attracted significant attention for mid-IR applications including optical sensing,spectroscopy,and nonlinear optics.However,mid-IR silicon PICs typically show moderate performance compared to state-of-the-art silicon photonic devices operating in the telecommunication band.Here,we proposed and demonstrated suspended nanomembrane silicon(SNS)PICs with light-guiding within deep-subwavelength waveguide thickness for operation in the short-wavelength mid-IR region.We demonstrated key building components,namely,grating couplers,waveguide arrays,micro-resonators,etc.,which exhibit excellent performances in bandwidths,back reflections,quality factors,and fabrication tolerance.Moreover,the results show that the proposed SNS PICs have high compatibility with the multi-project wafer foundry services.Our study provides an unprecedented platform for mid-IR integrated photonics and applications.展开更多
We provide an overview of our recent work on developing subwavelength grating （SWG） waveguide devices as an enabling technology for integrated microwave photonics. First, we describe wavelength-selective SWG wavegui...We provide an overview of our recent work on developing subwavelength grating （SWG） waveguide devices as an enabling technology for integrated microwave photonics. First, we describe wavelength-selective SWG waveguide filters, including ring resonators, Bragg gratings, and contradirectional couplers. Second, we discuss the development of an index variable optical true time delay line that exploits spatial diversity in an equal-length waveguide array. These SWG waveguide components are fundamental building blocks for realizing more complex structures for advanced microwave photonic signal processing.展开更多
The fabrication and characterization of p-i-n photodiodes integrated with wide spectrum focusing reflectors using nonperiodic strip and concentric-circular subwavelength gratings are presented. The experimental result...The fabrication and characterization of p-i-n photodiodes integrated with wide spectrum focusing reflectors using nonperiodic strip and concentric-circular subwavelength gratings are presented. The experimental results show that the gratings can reflect and focus the incident light on the absorber of the photodiode, and thus can simultaneously achieve high speed and high efficiency. For the gratings’ integrated photodiodes, the responsivity is improved over a wide spectral range, and when the absorber was 600 nm and the mesa diameter was40 μm, a responsivity of 0.46 A/W at a wavelength of 1.55 μm and a 3 dB bandwidth of 21.6 GHz under a reverse bias of 3 V were simultaneously obtained.展开更多
A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The propos...A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength （λ0） divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.展开更多
With the support by the National Natural Science Foundation of China,a collaboration by the research groups led by Prof.Cheng Gang(程纲)from Henan University and Prof.Wang Zhonglin(王中林)from Beijing Institute of Nan...With the support by the National Natural Science Foundation of China,a collaboration by the research groups led by Prof.Cheng Gang(程纲)from Henan University and Prof.Wang Zhonglin(王中林)from Beijing Institute of Nanoenergy and Nanosystems,Chinese Academy of Sciences,invents'a sliding-mode triboelectric nanogenerator with chemical group grated structure by shadow mask reactive ion etching',which was published in ACS Nano(2017,11(9):8796-8803).展开更多
An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） s...An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） substrate.The experimental results demonstrate that the MR propagation loss is 0.532 dB/cm with a 10μm radius ring resonator,the intrinsic quality factor is as high as 202.000,the waveguide grating wavelength response curve is a 1 dB bandwidth of 40 nm at 1540 nm telecommunication wavelengths,and the measured fiber-to-fiber coupling loss is 10 dB.Furthermore,the resonator wavelength temperature dependence of the 450 nm wide micro-ring resonator is 54.1 pm/℃.Such vertical grating coupler and low loss MR-integrated components greatly promote a key element in biosensors and high-speed interconnect communication applications.展开更多
The design and fabrication of a compact and low-cost 4×25-Gb/s transmitter optical sub-assembly(TOSA) and receiver optical sub-assembly(ROSA) using a hybrid integrated technique are reported. TOSA and ROSA are de...The design and fabrication of a compact and low-cost 4×25-Gb/s transmitter optical sub-assembly(TOSA) and receiver optical sub-assembly(ROSA) using a hybrid integrated technique are reported. TOSA and ROSA are developed without thermoelectric cooler for coarse wavelength division multiplexing applications. Physical dimension of the packaged optical subassembly is limited to 11.5 mm×5.4 mm×5.4 mm. The design of TOSA and ROSA is employed using a silica-based arrayed waveguide grating chip to select the specific channel wavelength at O-band. In TOSA, the wavelength of four 1.3-μm discrete directly modulated laser chips is well controlled based on the reconstruction equivalent chirp technique. In the back-to-back transmission test, bit error rates for all lanes of cascade of the TOSA and ROSA are small. A clear opening eye diagram is obtained.展开更多
A planar-integrated optical system(PIOS)represents powerful optical imaging and information processing techniques and is a potential candidate for the realization of a three-dimensional(3D)integrated optoelectronic in...A planar-integrated optical system(PIOS)represents powerful optical imaging and information processing techniques and is a potential candidate for the realization of a three-dimensional(3D)integrated optoelectronic intelligent system.Coupling the optical wave carrying information into a planar transparent substrate(typically fused silica)is an essential prerequisite for the realization of such a PIOS.Unlike conventional grating couplers for nano-waveguides on the silicon-on-insulator platform,the grating couplers for PIOS enable to obtain a higher design freedom and to achieve much higher coupling efficiency.By combining the rigorous coupled wave algorithm and simulated annealing optimization algorithm,a highefficiency asymmetric double-groove grating coupler is designed for PIOS.It is indicated that,under the condition of the normal incidence of TE polarization,the diffraction efficiency of the-1st order is over 95%,and its average value is 97.3%and 92.8%in the C and C+L bands.The simulation results indicate that this type of grating coupler has good tolerance and is expected to be applied in optical interconnections,waveguide-based augmented reality glasses,and planar-integrated 3D interconnection optical computing systems.展开更多
基金sponsored by the National Key Scientific Instrument and Equipment Development Projects of China(Grant No.62027823)the National Natural Science Foun-dation of China(Grant No.61775048).
文摘In recent years,the use of deep learning to replace traditional numerical methods for electromagnetic propagation has shown tremendous potential in the rapid design of photonic devices.However,most research on deep learning has focused on single-layer grating couplers,and the accuracy of multi-layer grating couplers has not yet reached a high level.This paper proposes and demonstrates a novel deep learning network-assisted strategy for inverse design.The network model is based on a multi-layer perceptron(MLP)and incorporates convolutional neural networks(CNNs)and transformers.Through the stacking of multiple layers,it achieves a high-precision design for both multi-layer and single-layer raster couplers with various functionalities.The deep learning network exhibits exceptionally high predictive accuracy,with an average absolute error across the full wavelength range of 1300–1700 nm being only 0.17%,and an even lower predictive absolute error below 0.09%at the specific wavelength of 1550 nm.By combining the deep learning network with the genetic algorithm,we can efficiently design grating couplers that perform different functions.Simulation results indicate that the designed single-wavelength grating couplers achieve coupling efficiencies exceeding 80%at central wavelengths of 1550 nm and 1310 nm.The performance of designed dual-wavelength and broadband grating couplers also reaches high industry standards.Furthermore,the network structure and inverse design method are highly scalable and can be applied not only to multi-layer grating couplers but also directly to the prediction and design of single-layer grating couplers,providing a new perspective for the innovative development of photonic devices.
基金Project supported by the National Key R&D Program of China(Grant Nos.2021YFA1402004 and 2021YFF0603701)the National Natural Science Foundation of China(Grant Nos.12134014,U21A20433,U21A6006,and 92265108)+1 种基金supported by the Fundamental Research Funds for the Central UniversitiesUSTC Research Funds of the Double First-Class Initiative。
文摘We experimentally investigate the effective working regions of a planar-integrated magneto-optical trap(MOT).By scanning a blocking point in the incident laser beam,we identify four effective working regions of the laser beam contributing to MOT:a central region corresponding to the downward incident beam and three regions associated with the upward diffracted beams.The latter three regions are the effective regions of the grating chip.It is demonstrated that only three3.5 mm radius grating regions can produce a MOT that is capable of trapping 105atoms with a temperature below 150μK,retaining over 60%of atoms compared to a complete grating chip.This finding suggests that more than 60%of the grating chip area can be saved for other on-chip components,such as metasurfaces and nanophotonic devices,without significantly compromising MOT performance,paving the way for more compact and versatile atom–photon interfaces.
基金This work was supported by National Natural Science Foundation of China(No.U19B2028).
文摘A scanning and uniform array architecture with large spacing,low complexity and high scalability is presented for high integration massive array applications.It is constructed by offset phase center elements arranged in a uniform and regular way,but its spacing can be larger than that of traditional arrays.An ideal model of the offset phase center element is established and its far-field distribution is derived.To suppress grating lobes,the phase center of any element is designed to be movable without changing its physical position.Using genetic algorithm(GA),a new constraint condition limiting the number of phase center changes is proposed to solve the objective function of the minimum values of grating lobes(GLs)and side lobes(SLs).It is shown that the optimal results can be achieved by two changes of phase centers.A multimode circular patch is developed and designed,and characteristics of the offset phase center are analyzed and verified.A prototype array of 12×12 offset phase center elements is implemented based on multi-mode circular patches.Full wave simulation results of radiation patterns show that the level of grating lobes is suppressed at least 7dB with 1.12λ spacing,while the scanning angle is 20°.
基金the National Natural Science Foundation of China(Nos.12004353,11975214,11991071,11905202,12174350)Key Laboratory Foundation of The Sciences and Technology on Plasma Physics Laboratory(No.6142A04200103)Independent scientific research(No.JCKYS2021212011).
文摘Particle accelerators are indispensable tools in both science and industry.However,the size and cost of conventional RF accelerators limits the utility and scope of this technology.Recent research has shown that a dielectric laser accelerator(DLA)made of dielectric structures and driven at optical frequencies can generate particle beams with energies ranging from MeV to GeV at the tabletop level.To design DLA structures with a high acceleration gradient,we demonstrate topology optimization,which is a method used to optimize the material distribution in a specific area based on given load conditions,constraints,and performance indicators.To demonstrate the effectiveness of this approach,we propose two schemes and design several acceleration structures based on them.The optimization results demonstrate that the proposed method can be applied to structure optimization for on-chip integrated laser accelerators,producing manufacturable structures with significantly improved performance compared with previous size or shape optimization methods.These results provide new physical approaches to explore ultrafast dynamics in matter,with important implications for future laser particle accelerators based on photonic chips.
文摘A modified multiwavelength actively mode-locked fiber ring laser is proposed and experimentally demonstrated. In this kind of laser, stable multiwavelengths lasing is achieved by integrating cascaded sampled fiber Bragg gratings(SFBGs) into the laser cavity. To implement actively mode-locking technique, a double-ring cavity configuration is used to assure that the cavity lengths for all wavelengths lasing are identical. Thus, simultaneous mode locking of all wavelengths has been successfully achieved by using the same mode-locking signal.
文摘This paper introduces the design and applications of integrated As2S3 sidewall Bragg gratings on LiNbO3 substrate. The grating reflectance and bandwidth are analyzed with coupled-mode theory. Coupling coefficients are computed by taking overlap integration. Numerical results for uniform gratings, phase-shifted gratings and grating cavities as well as electro-optic tunable gratings are presented. These integrated As2S3 sidewall gratings on LiNbO3 substrate provide an approach to the design of a wide range of integrated optical devices including switches, laser cavities, modulators, sensors and tunable filters.
文摘Effectively managing floods in urban regions requires effectively designed and well-maintained runoff collection system. The absence of such a system and intense rainfall event will have the potential to disrupt the urban life and cause significant economic loss to properties. Grated inlets, which are a key component in urban drainage network, are used to capture the runoff. In this work, a three dimensional CFD model was developed based on open-source CFD tool, OpenFOAM®, to model flow over a grated inlet. An incompressible, transient, multiphase flow, Volume of Fluid (VOF) simulation was performed to predict the water flow rate through the grate inlet. The predicted flow rates are compared with the HEC-22 monograph values. The close agreement between the results shows the potential of using CFD modeling approach to test the reliability of existing drainage inlets for different flow scenarios.
基金supported by NSF Convergence Accelerator Track I:FUTUR-IC:A Resource-Efficient Microchip Manufacturing and Operations Research Alliance,Award Number ITE-2345076.
文摘In this paper,we provide an overview and comparison of devices used for optical waveguide-to-waveguide coupling including inter-chip edge couplers,grating couplers,free form couplers,evanescent couplers,cantilever couplers,and optical wirebonds.In addition,technology for efficient transmission of light through chips is discussed including guided mode and free form photonic vias for substrates including silicon,glass,and organics.The results are discussed in the context of potential applications including co-packaged optics switch packages,replaceable biochemical sensors,optically connected memory,optical computing,integrated quantum photonics,and integrated LiDAR systems to show possible improvements in energy efficiency,performance,and cost.
基金supported by National Natural Science Foundation of China(NO.62275142)Shenzhen Stability Support Program Project(NO.WDZC 20231124201906001)Guangdong Basic and Applied Research Fund(NO.2021B1515120007).
文摘This study proposes a novel heterodyne grating interferometer designed to meet the multi-dimensional atomiclevel measurement demands of next-generation lithography systems and large-scale atomic-level manufacturing.By utilizing a dual-frequency laser source,the interferometer enables simultaneous three-degree-of-freedom(3-DOF)displacement measurements.Key innovations include a compact,zero dead-zone optical path architecture,which enhances measurement robustness by minimizing sensitivity to laser source instabilities and atmospheric refractive index fluctuations.In addition,we present a systematic crosstalk error analysis,coupled with a corresponding compensation algorithm,effectively reducing crosstalk-induced errors to below 5%.Experimental evaluation of the 90×90×40 mm^(3) prototype demonstrates outstanding performance metrics:sub-nanometer resolutions(0.25 nm for X/Y-axes,0.3 nm for Z-axis),superior linearity coefficients(6.9×10^(−5),8.1×10^(−5),16.2×10^(−5) for X-,Y-,and Z-axes,respectively),high repeatability(0.8 nm@1000 nm for all axes),exceptional long-term stability(20 nm XY-plane drift,60 nm Z-axis drift over 1000 s),and practical measurement ranges exceeding 10 mm inplane and 2 mm axially.Comparative analysis with state-of-the-art sensors demonstrates significant advantages in measurement precision,system integration,and multi-axis capability.This advancement highlights excellent potential for applications in integrated circuit fabrication,atomic-scale manufacturing,and ultra-precision metrology for aerospace systems.
基金supported by the National Basic Research Program of China(No.2011CBA00608)the National Natural Science Foundation of China(Nos.61178051,61321063,61335010,61178048,61275169)the National High Technology Research and Development Program of China(Nos.2013AA013602,2013AA031903,2013AA032204)
文摘Silicon photonics is an emerging competitive solution for next-generation scalable data communications in different application areas as high-speed data communication is constrained by electrical interconnects. Optical interconnects based on silicon photonics can be used in intra/inter-chip interconnects, board-to-board interconnects, short-reach communications in datacenters, supercomputers and long-haul optical transmissions. In this paper, we present an overview of recent progress in silicon optoelectronic devices and optoelectronic integrated circuits （OEICs） based on a complementary metal-oxide-semiconductor-compatible process, and focus on our research contributions. The silicon optoelectronic devices and OEICs show good characteristics, which are expected to benefit several application domains, including communication, sensing, computing and nonlinear systems.
基金partly supported by the National Natural Science Foundation of China(NSFC)(62175179,62161160335)Natural Science Foundation of Tianjin Municipality,China(23JCJQJC00250)+1 种基金Natural Science Foundation of Guangdong Province,China(2022B1515130002,2023A1515011189)Japan Society for the Promotion of Science(JSPS)(JP18K13798).
文摘Leveraging the low linear and nonlinear absorption loss of silicon at mid-infrared(mid-IR)wavelengths,silicon photonic integrated circuits(PICs)have attracted significant attention for mid-IR applications including optical sensing,spectroscopy,and nonlinear optics.However,mid-IR silicon PICs typically show moderate performance compared to state-of-the-art silicon photonic devices operating in the telecommunication band.Here,we proposed and demonstrated suspended nanomembrane silicon(SNS)PICs with light-guiding within deep-subwavelength waveguide thickness for operation in the short-wavelength mid-IR region.We demonstrated key building components,namely,grating couplers,waveguide arrays,micro-resonators,etc.,which exhibit excellent performances in bandwidths,back reflections,quality factors,and fabrication tolerance.Moreover,the results show that the proposed SNS PICs have high compatibility with the multi-project wafer foundry services.Our study provides an unprecedented platform for mid-IR integrated photonics and applications.
基金supported in part by the Natural Sciences and Engineering Research Council of Canadathe Fonds de Recherche du Québec-Nature et Technologies,and the Royal Society
文摘We provide an overview of our recent work on developing subwavelength grating （SWG） waveguide devices as an enabling technology for integrated microwave photonics. First, we describe wavelength-selective SWG waveguide filters, including ring resonators, Bragg gratings, and contradirectional couplers. Second, we discuss the development of an index variable optical true time delay line that exploits spatial diversity in an equal-length waveguide array. These SWG waveguide components are fundamental building blocks for realizing more complex structures for advanced microwave photonic signal processing.
基金funded by the National Natural Science Foundation of China(NSFC)(Nos.61574019,61674020,and 61274044)the 111 Project(No.B07005)+2 种基金the Beijing Municipality Natural Science Foundation(No.4132069)the Program for Changjiang ScholarsInnovative Research Team in University through the Ministry of Education of China(No.IRT0609)
文摘The fabrication and characterization of p-i-n photodiodes integrated with wide spectrum focusing reflectors using nonperiodic strip and concentric-circular subwavelength gratings are presented. The experimental results show that the gratings can reflect and focus the incident light on the absorber of the photodiode, and thus can simultaneously achieve high speed and high efficiency. For the gratings’ integrated photodiodes, the responsivity is improved over a wide spectral range, and when the absorber was 600 nm and the mesa diameter was40 μm, a responsivity of 0.46 A/W at a wavelength of 1.55 μm and a 3 dB bandwidth of 21.6 GHz under a reverse bias of 3 V were simultaneously obtained.
基金Grant number LRGS(2015)NGOD/UM/KPT,RU007/2015 and RUG OF UTM,09H77 and 10J97 from the university of Malaya (UM) and Universiti Teknologi Malaysia (UTM)
文摘A system of an add-drop microring resonator integrated with a sampled grating distributed feedback （SG-DFB） is investigated via modeling and simulation with the time-domain traveling wave （TDTW） method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr co- efficient of 4.5 × 10^-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and I0 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength （λ0） divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 10^5 and 2.87 × 10^5, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.
文摘With the support by the National Natural Science Foundation of China,a collaboration by the research groups led by Prof.Cheng Gang(程纲)from Henan University and Prof.Wang Zhonglin(王中林)from Beijing Institute of Nanoenergy and Nanosystems,Chinese Academy of Sciences,invents'a sliding-mode triboelectric nanogenerator with chemical group grated structure by shadow mask reactive ion etching',which was published in ACS Nano(2017,11(9):8796-8803).
基金supported by the National Basic Research Program of China(No.2009CB326206)the National Natural Science Foundation of China(Nos.61076111,50975266)+2 种基金the Key Laboratory Fund of China(No.9140C1204040909)the Graduate Innovation Project of China (No.20103083)the Fund for Top Young Academic Leaders of Higher Learning Institutions of Shanxi(TYAL),China
文摘An ultra-small integrated photonic circuit has been proposed,which incorporates a high-quality-factor passive micro-ring resonator（MR） linked to a vertical grating coupler on a standard silicon-on-insulator（SOI） substrate.The experimental results demonstrate that the MR propagation loss is 0.532 dB/cm with a 10μm radius ring resonator,the intrinsic quality factor is as high as 202.000,the waveguide grating wavelength response curve is a 1 dB bandwidth of 40 nm at 1540 nm telecommunication wavelengths,and the measured fiber-to-fiber coupling loss is 10 dB.Furthermore,the resonator wavelength temperature dependence of the 450 nm wide micro-ring resonator is 54.1 pm/℃.Such vertical grating coupler and low loss MR-integrated components greatly promote a key element in biosensors and high-speed interconnect communication applications.
基金Project supported by the National Natural Science Foundation of China(Nos.61635001 and 61575186)the National High-Tech R&D Program of China(863 Program)(No.2013AA014201)
文摘The design and fabrication of a compact and low-cost 4×25-Gb/s transmitter optical sub-assembly(TOSA) and receiver optical sub-assembly(ROSA) using a hybrid integrated technique are reported. TOSA and ROSA are developed without thermoelectric cooler for coarse wavelength division multiplexing applications. Physical dimension of the packaged optical subassembly is limited to 11.5 mm×5.4 mm×5.4 mm. The design of TOSA and ROSA is employed using a silica-based arrayed waveguide grating chip to select the specific channel wavelength at O-band. In TOSA, the wavelength of four 1.3-μm discrete directly modulated laser chips is well controlled based on the reconstruction equivalent chirp technique. In the back-to-back transmission test, bit error rates for all lanes of cascade of the TOSA and ROSA are small. A clear opening eye diagram is obtained.
基金supported by the Shanghai Science and Technology Committee(Nos.19JC1415400,19DZ1191102,and 20ZR1464700)in part by the Cutting-Edge Sciences Important Research Program,Bureau of Frontier Sciences and Education,Chinese Academy of Sciences(No.QYZDJSSW-JSC014)。
文摘A planar-integrated optical system(PIOS)represents powerful optical imaging and information processing techniques and is a potential candidate for the realization of a three-dimensional(3D)integrated optoelectronic intelligent system.Coupling the optical wave carrying information into a planar transparent substrate(typically fused silica)is an essential prerequisite for the realization of such a PIOS.Unlike conventional grating couplers for nano-waveguides on the silicon-on-insulator platform,the grating couplers for PIOS enable to obtain a higher design freedom and to achieve much higher coupling efficiency.By combining the rigorous coupled wave algorithm and simulated annealing optimization algorithm,a highefficiency asymmetric double-groove grating coupler is designed for PIOS.It is indicated that,under the condition of the normal incidence of TE polarization,the diffraction efficiency of the-1st order is over 95%,and its average value is 97.3%and 92.8%in the C and C+L bands.The simulation results indicate that this type of grating coupler has good tolerance and is expected to be applied in optical interconnections,waveguide-based augmented reality glasses,and planar-integrated 3D interconnection optical computing systems.
